#include <linux/sched/cond_resched.h>
#include <linux/sched/cputime.h>
#include <linux/sched/isolation.h>
+#include <linux/sched/nohz.h>
#include <linux/cpuidle.h>
#include <linux/interrupt.h>
*
* (default: 5 msec, units: microseconds)
*/
-unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
+static unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
+#endif
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table sched_fair_sysctls[] = {
+ {
+ .procname = "sched_child_runs_first",
+ .data = &sysctl_sched_child_runs_first,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+#ifdef CONFIG_CFS_BANDWIDTH
+ {
+ .procname = "sched_cfs_bandwidth_slice_us",
+ .data = &sysctl_sched_cfs_bandwidth_slice,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ONE,
+ },
+#endif
+ {}
+};
+
+static int __init sched_fair_sysctl_init(void)
+{
+ register_sysctl_init("kernel", sched_fair_sysctls);
+ return 0;
+}
+late_initcall(sched_fair_sysctl_init);
#endif
static inline void update_load_add(struct load_weight *lw, unsigned long inc)
#define for_each_sched_entity(se) \
for (; se; se = se->parent)
-static inline void cfs_rq_tg_path(struct cfs_rq *cfs_rq, char *path, int len)
-{
- if (!path)
- return;
-
- if (cfs_rq && task_group_is_autogroup(cfs_rq->tg))
- autogroup_path(cfs_rq->tg, path, len);
- else if (cfs_rq && cfs_rq->tg->css.cgroup)
- cgroup_path(cfs_rq->tg->css.cgroup, path, len);
- else
- strlcpy(path, "(null)", len);
-}
-
static inline bool list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
struct rq *rq = rq_of(cfs_rq);
#define for_each_sched_entity(se) \
for (; se; se = NULL)
-static inline void cfs_rq_tg_path(struct cfs_rq *cfs_rq, char *path, int len)
-{
- if (path)
- strlcpy(path, "(null)", len);
-}
-
static inline bool list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
return true;
se->avg.runnable_sum = se->avg.runnable_avg * divider;
- se->avg.load_sum = divider;
- if (se_weight(se)) {
- se->avg.load_sum =
- div_u64(se->avg.load_avg * se->avg.load_sum, se_weight(se));
- }
+ se->avg.load_sum = se->avg.load_avg * divider;
+ if (se_weight(se) < se->avg.load_sum)
+ se->avg.load_sum = div_u64(se->avg.load_sum, se_weight(se));
+ else
+ se->avg.load_sum = 1;
enqueue_load_avg(cfs_rq, se);
cfs_rq->avg.util_avg += se->avg.util_avg;
cfs_rq->throttle_count--;
if (!cfs_rq->throttle_count) {
- cfs_rq->throttled_clock_task_time += rq_clock_task(rq) -
- cfs_rq->throttled_clock_task;
+ cfs_rq->throttled_clock_pelt_time += rq_clock_pelt(rq) -
+ cfs_rq->throttled_clock_pelt;
/* Add cfs_rq with load or one or more already running entities to the list */
- if (!cfs_rq_is_decayed(cfs_rq) || cfs_rq->nr_running)
+ if (!cfs_rq_is_decayed(cfs_rq))
list_add_leaf_cfs_rq(cfs_rq);
}
/* group is entering throttled state, stop time */
if (!cfs_rq->throttle_count) {
- cfs_rq->throttled_clock_task = rq_clock_task(rq);
+ cfs_rq->throttled_clock_pelt = rq_clock_pelt(rq);
list_del_leaf_cfs_rq(cfs_rq);
}
cfs_rq->throttle_count++;
pcfs_rq = tg->parent->cfs_rq[cpu];
cfs_rq->throttle_count = pcfs_rq->throttle_count;
- cfs_rq->throttled_clock_task = rq_clock_task(cpu_rq(cpu));
+ cfs_rq->throttled_clock_pelt = rq_clock_pelt(cpu_rq(cpu));
}
/* conditionally throttle active cfs_rq's from put_prev_entity() */
}
/*
- * cpu_util_without: compute cpu utilization without any contributions from *p
- * @cpu: the CPU which utilization is requested
- * @p: the task which utilization should be discounted
- *
- * The utilization of a CPU is defined by the utilization of tasks currently
- * enqueued on that CPU as well as tasks which are currently sleeping after an
- * execution on that CPU.
- *
- * This method returns the utilization of the specified CPU by discounting the
- * utilization of the specified task, whenever the task is currently
- * contributing to the CPU utilization.
- */
-static unsigned long cpu_util_without(int cpu, struct task_struct *p)
-{
- struct cfs_rq *cfs_rq;
- unsigned int util;
-
- /* Task has no contribution or is new */
- if (cpu != task_cpu(p) || !READ_ONCE(p->se.avg.last_update_time))
- return cpu_util_cfs(cpu);
-
- cfs_rq = &cpu_rq(cpu)->cfs;
- util = READ_ONCE(cfs_rq->avg.util_avg);
-
- /* Discount task's util from CPU's util */
- lsub_positive(&util, task_util(p));
-
- /*
- * Covered cases:
- *
- * a) if *p is the only task sleeping on this CPU, then:
- * cpu_util (== task_util) > util_est (== 0)
- * and thus we return:
- * cpu_util_without = (cpu_util - task_util) = 0
- *
- * b) if other tasks are SLEEPING on this CPU, which is now exiting
- * IDLE, then:
- * cpu_util >= task_util
- * cpu_util > util_est (== 0)
- * and thus we discount *p's blocked utilization to return:
- * cpu_util_without = (cpu_util - task_util) >= 0
- *
- * c) if other tasks are RUNNABLE on that CPU and
- * util_est > cpu_util
- * then we use util_est since it returns a more restrictive
- * estimation of the spare capacity on that CPU, by just
- * considering the expected utilization of tasks already
- * runnable on that CPU.
- *
- * Cases a) and b) are covered by the above code, while case c) is
- * covered by the following code when estimated utilization is
- * enabled.
- */
- if (sched_feat(UTIL_EST)) {
- unsigned int estimated =
- READ_ONCE(cfs_rq->avg.util_est.enqueued);
-
- /*
- * Despite the following checks we still have a small window
- * for a possible race, when an execl's select_task_rq_fair()
- * races with LB's detach_task():
- *
- * detach_task()
- * p->on_rq = TASK_ON_RQ_MIGRATING;
- * ---------------------------------- A
- * deactivate_task() \
- * dequeue_task() + RaceTime
- * util_est_dequeue() /
- * ---------------------------------- B
- *
- * The additional check on "current == p" it's required to
- * properly fix the execl regression and it helps in further
- * reducing the chances for the above race.
- */
- if (unlikely(task_on_rq_queued(p) || current == p))
- lsub_positive(&estimated, _task_util_est(p));
-
- util = max(util, estimated);
- }
-
- /*
- * Utilization (estimated) can exceed the CPU capacity, thus let's
- * clamp to the maximum CPU capacity to ensure consistency with
- * cpu_util.
- */
- return min_t(unsigned long, util, capacity_orig_of(cpu));
-}
-
-/*
- * Predicts what cpu_util(@cpu) would return if @p was migrated (and enqueued)
- * to @dst_cpu.
+ * Predicts what cpu_util(@cpu) would return if @p was removed from @cpu
+ * (@dst_cpu = -1) or migrated to @dst_cpu.
*/
static unsigned long cpu_util_next(int cpu, struct task_struct *p, int dst_cpu)
{
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
- unsigned long util_est, util = READ_ONCE(cfs_rq->avg.util_avg);
+ unsigned long util = READ_ONCE(cfs_rq->avg.util_avg);
/*
- * If @p migrates from @cpu to another, remove its contribution. Or,
- * if @p migrates from another CPU to @cpu, add its contribution. In
- * the other cases, @cpu is not impacted by the migration, so the
- * util_avg should already be correct.
+ * If @dst_cpu is -1 or @p migrates from @cpu to @dst_cpu remove its
+ * contribution. If @p migrates from another CPU to @cpu add its
+ * contribution. In all the other cases @cpu is not impacted by the
+ * migration so its util_avg is already correct.
*/
if (task_cpu(p) == cpu && dst_cpu != cpu)
lsub_positive(&util, task_util(p));
util += task_util(p);
if (sched_feat(UTIL_EST)) {
+ unsigned long util_est;
+
util_est = READ_ONCE(cfs_rq->avg.util_est.enqueued);
/*
- * During wake-up, the task isn't enqueued yet and doesn't
- * appear in the cfs_rq->avg.util_est.enqueued of any rq,
- * so just add it (if needed) to "simulate" what will be
- * cpu_util after the task has been enqueued.
+ * During wake-up @p isn't enqueued yet and doesn't contribute
+ * to any cpu_rq(cpu)->cfs.avg.util_est.enqueued.
+ * If @dst_cpu == @cpu add it to "simulate" cpu_util after @p
+ * has been enqueued.
+ *
+ * During exec (@dst_cpu = -1) @p is enqueued and does
+ * contribute to cpu_rq(cpu)->cfs.util_est.enqueued.
+ * Remove it to "simulate" cpu_util without @p's contribution.
+ *
+ * Despite the task_on_rq_queued(@p) check there is still a
+ * small window for a possible race when an exec
+ * select_task_rq_fair() races with LB's detach_task().
+ *
+ * detach_task()
+ * deactivate_task()
+ * p->on_rq = TASK_ON_RQ_MIGRATING;
+ * -------------------------------- A
+ * dequeue_task() \
+ * dequeue_task_fair() + Race Time
+ * util_est_dequeue() /
+ * -------------------------------- B
+ *
+ * The additional check "current == p" is required to further
+ * reduce the race window.
*/
if (dst_cpu == cpu)
util_est += _task_util_est(p);
+ else if (unlikely(task_on_rq_queued(p) || current == p))
+ lsub_positive(&util_est, _task_util_est(p));
util = max(util, util_est);
}
return min(util, capacity_orig_of(cpu));
}
+/*
+ * cpu_util_without: compute cpu utilization without any contributions from *p
+ * @cpu: the CPU which utilization is requested
+ * @p: the task which utilization should be discounted
+ *
+ * The utilization of a CPU is defined by the utilization of tasks currently
+ * enqueued on that CPU as well as tasks which are currently sleeping after an
+ * execution on that CPU.
+ *
+ * This method returns the utilization of the specified CPU by discounting the
+ * utilization of the specified task, whenever the task is currently
+ * contributing to the CPU utilization.
+ */
+static unsigned long cpu_util_without(int cpu, struct task_struct *p)
+{
+ /* Task has no contribution or is new */
+ if (cpu != task_cpu(p) || !READ_ONCE(p->se.avg.last_update_time))
+ return cpu_util_cfs(cpu);
+
+ return cpu_util_next(cpu, p, -1);
+}
+
/*
* compute_energy(): Estimates the energy that @pd would consume if @p was
* migrated to @dst_cpu. compute_energy() predicts what will be the utilization
local->avg_load = (local->group_load * SCHED_CAPACITY_SCALE) /
local->group_capacity;
- sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) /
- sds->total_capacity;
/*
* If the local group is more loaded than the selected
* busiest group don't try to pull any tasks.
env->imbalance = 0;
return;
}
+
+ sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) /
+ sds->total_capacity;
}
/*
* busiest \ local has_spare fully_busy misfit asym imbalanced overloaded
* has_spare nr_idle balanced N/A N/A balanced balanced
* fully_busy nr_idle nr_idle N/A N/A balanced balanced
- * misfit_task force N/A N/A N/A force force
+ * misfit_task force N/A N/A N/A N/A N/A
* asym_packing force force N/A N/A force force
* imbalanced force force N/A N/A force force
* overloaded force force N/A N/A force avg_load
#endif /* SMP */
}
-
-/*
- * Helper functions to facilitate extracting info from tracepoints.
- */
-
-const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq)
-{
-#ifdef CONFIG_SMP
- return cfs_rq ? &cfs_rq->avg : NULL;
-#else
- return NULL;
-#endif
-}
-EXPORT_SYMBOL_GPL(sched_trace_cfs_rq_avg);
-
-char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len)
-{
- if (!cfs_rq) {
- if (str)
- strlcpy(str, "(null)", len);
- else
- return NULL;
- }
-
- cfs_rq_tg_path(cfs_rq, str, len);
- return str;
-}
-EXPORT_SYMBOL_GPL(sched_trace_cfs_rq_path);
-
-int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq)
-{
- return cfs_rq ? cpu_of(rq_of(cfs_rq)) : -1;
-}
-EXPORT_SYMBOL_GPL(sched_trace_cfs_rq_cpu);
-
-const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq)
-{
-#ifdef CONFIG_SMP
- return rq ? &rq->avg_rt : NULL;
-#else
- return NULL;
-#endif
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_avg_rt);
-
-const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq)
-{
-#ifdef CONFIG_SMP
- return rq ? &rq->avg_dl : NULL;
-#else
- return NULL;
-#endif
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_avg_dl);
-
-const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq)
-{
-#if defined(CONFIG_SMP) && defined(CONFIG_HAVE_SCHED_AVG_IRQ)
- return rq ? &rq->avg_irq : NULL;
-#else
- return NULL;
-#endif
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_avg_irq);
-
-int sched_trace_rq_cpu(struct rq *rq)
-{
- return rq ? cpu_of(rq) : -1;
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_cpu);
-
-int sched_trace_rq_cpu_capacity(struct rq *rq)
-{
- return rq ?
-#ifdef CONFIG_SMP
- rq->cpu_capacity
-#else
- SCHED_CAPACITY_SCALE
-#endif
- : -1;
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_cpu_capacity);
-
-const struct cpumask *sched_trace_rd_span(struct root_domain *rd)
-{
-#ifdef CONFIG_SMP
- return rd ? rd->span : NULL;
-#else
- return NULL;
-#endif
-}
-EXPORT_SYMBOL_GPL(sched_trace_rd_span);
-
-int sched_trace_rq_nr_running(struct rq *rq)
-{
- return rq ? rq->nr_running : -1;
-}
-EXPORT_SYMBOL_GPL(sched_trace_rq_nr_running);
projects / linux-2.6-microblaze.git / blobdiff